Late Apple co-founder Steve Jobs is the subject of debate in a case involving major technology companies and their alleged efforts to not poach employees from each other.

Tech employees represented in a class-action lawsuit against Apple, Google, Intel, and Adobe petitioned US District Court Judge Lucy Koh on Thursday to allow any and all Jobs-related evidence discovered in the course of the trial to be admissible in their ongoing fight with the tech giants, according to Reuters.

The move comes after the four companies asked Judge Koh to limit evidence against Jobs. The companies were fine with the plaintiffs including e-mails and other communications sent related to the alleged agreements between the firms, but not comments made in ancillary sources, such as Walter Isaacson's biography of Jobs.

The battle between the firms dates back to 2011 when a class-action lawsuit was launched against the four heavyweight tech firms by industry employees who claim that the companies worked together to limit employee poaching and stave off a wage war. If the class, which represents approximately 64,000 people, is victorious, the companies could be forced to pay $3 billion in damages.

At the center of the case is an email exchange between Jobs and Google's executive chairman, Eric Schmidt. According to court documents obtained by Reuters, Jobs complained to Schmidt about a Google recruiter trying to poach Apple employees, and was told by the then-Google CEO that the person would be fired. Jobs forwarded Schmidt's message to one of his human resources people with an attached smiley face.

According to Reuters, the class argues that accounts of Jobs in ancillary sources like the Isaacson book might present insight into "Mr. Jobs' character."

The trial between the class and the companies is set for May. It's possible, however, that the sides could settle before that date is reached. Walt Disney's Pixar (which was formerly owned by Jobs), along with Lucasfilm and Intuit, were also cited in the lawsuit but have already settled with the class.

CNET has contacted Apple and Google for comment on the report. We will update this story when we have more information.